ELSM Hello Messages
ELSM uses two types of hello messages to communicate the health of the
network to other ELSM ports. The following describes the hello messages:
- Hello+ — The ELSM-enabled port receives a hello message from its
peer and no problem is detected.
- Hello- — The ELSM-enabled port has not received a hello message
from its peer.
In addition to the ELSM port states described in the next section, ELSM
has hello transmit states. The hello transmit states display the current state of
transmitted ELSM hello messages and can be one of the following:
- HelloRx(+)—The ELSM-enabled port is up and receives Hello+
messages from its peer. The port remains in the HelloRx+ state and restarts the
HelloRx timer each time it receives a Hello+ message. If the HelloRx timer expires,
the hello transmit state enters HelloRx(-). The HelloRx timer is 6 * hello timer,
which by default is 6 seconds.
- HelloRx(-)—The ELSM-enabled port either transitions from the
initial ELSM state or is up but has not received hello messages because there is a
problem with the link or the peer is missing.
For information about displaying ELSM hello messages and hello transmit
states, see Displaying ELSM Information.
